【摘要】 黑河上游冻土面积 (6 5 0 0 km2 )约占流域面积的 45 %,对水资源形成和稳定性有重要影响 ,多年冻土在世纪千年以上限制活动层的地下水系统 ,导致活动层土壤水分饱和 ,有利于提高植物蒸发对水的利用效率 ;同时多年冻土抑制水分向深层土壤的下渗 ,增加了径流深度和蒸腾发强度。由于多年冻土和季节冻土的影响黑河上游河川径流年内水文活动可分为三个时期 ,多年冻土区最大径流产生于融雪径流期。更多还原

【Abstract】 The area of frozen soil in the upper reaches of Heihe River occupies 45% of the catchments area. The frozen soil has great influence on formation and stability of water resources. Ever frozen ground restrains underground water system in activity layer over thousands of years, and it causes the saturation of soil water in the active layer, and contributes to improve the water using efficiency of plant evaporation. Ever frozen ground prevents water from infiltrating to deep layer, which increases the depth of runoff and intensity of transpiration. Annual hydrology activity of streamflow in the upper reaches of Heihe River can be divided into three periods due to the influence of ever frozen ground and seasonal frozen ground, and maximum runoff occurs during the snowmelt streamflow period in frozen ground.更多还原